This section contains a summary of Babylon 5's story arc (the 5-year
plotline) up to, but not including,
"The Quality of Mercy."
Note that this is chock full of spoilers!

The pilot, "The Gathering," was set in the year 2257;
Babylon 5 had recently come online. The last of the ambassadors,
Kosh, arrived on the station, prompting an assassination attempt. Sinclair
was framed for the attempt, but was eventually cleared when the real culprit
-- a Minbari -- was discovered. Many mysteries were introduced: Sinclair's
missing 24 hours on the Battle of the Line (with the announcement by the
Minbari that "there is a hole in your mind"); the mystery of Kosh, seen
only by the doctor and the telepath; and the disappearance or destruction
of the previous four Babylon stations.

More Recently...

Season One began with
"Midnight on the Firing Line,"
about 6 months later.
Lt. Cmdr Susan Ivanova replaced Lt. Cmdr. Takashima as second-in-command;
her dislike of the Psi Corps became evident when Talia Winters arrived.
A Centauri agricultural outpost was attacked without provocation by the Narns.
(In broad strokes, this episode portrayed the Narns as the "bad guys"
and the Centauri as comic relief.) Luis Santiago was reelected
President of the Earth Alliance.

A "Soul Hunter,"
a member of an order which collects and preserves important
souls, found himself on the station, and attempted to collect Delenn's soul
prematurely. The Minbari, it was revealed, greatly value souls; they
prevented a soul hunter from taking the soul of their great leader Dukhat,
so that his soul would be reborn into the next generation. Delenn was
called Satai by the soul hunter, which prompted Sinclair to wonder if
something was going on, as Satai is the title used my members of the Grey
Council, the Minbari ruling body and highest religious authority.

In
"Mind War,"
two Psi Cops -- P12 level telepaths, including Bester
(played by Walter Koenig) -- came to the station in search of telepath
Jason Ironheart, who had achieved telekinetic abilities and was transforming
into something more than human. Ironheart warned Sinclair that the Psi Corps
is starting to pull the strings in the government back on Earth. When Bester's
partner was killed, Sinclair made a new enemy. Before departing, Ironheart
gave Talia a gift: telekinesis, and maybe other abilities as well.

"The War Prayer"
introduced members of the Homeguard, an anti-alien
organization back on Earth.

"And The Sky Full of Stars"
explored what happened to Sinclair on the
Battle of the Line, 10 years before in the Earth-Minbari War. Interrogated
and forced to relive the battle, we saw Sinclair ram a
Minbari Cruiser, only to wake up on board, interrogated by the Grey
Council. He recognizes Delenn as one of the Grey Council. After escaping
from his interrogators, he chose not to reveal to Delenn that he remembered
part of his missing 24 hours.

"Deathwalker"
was a notorious war criminal from the Dilgar War, fought by
Earth and others several decades earlier. She had a substance she claimed
granted immortality -- but only at the cost of another's life. The Vorlons
destroyed her ship to prevent Earth from gaining the secret of immortality.

"Survivors"
pulled Garibaldi back into his alcoholism amid accusations of
sabotage. The real culprit was the Homeguard.

"Signs and Portents"
deals with an attack by raiders on the station. The B-story, in which
Londo acquired the long-lost symbol of his empire, the Eye, was more
important. A mysterious, polite man named Morden inquired, "What do you
want?" of the alien ambassadors, and seemed to like Londo's response --
for the Centauri to reclaim their lost empire -- the
best. The Eye was captured by the raiders, who were destroyed by a
mysterious ship that appeared out of the shadows. Morden returned the Eye to
Londo, "from friends you don't know you have."

In the two-parter,
"A Voice in the Wilderness,"
it was discovered that the
planet below B5 is not as dead as was thought. The
Mars colony broke out in rebellion. A dying alien was found controlling
vast, tremendously powerful machinery on the planet below.
Draal, an old friend of Delenn's, took charge of the machinery in the planet,
warning away all who would try to take it for themselves. The Mars rebellion
was put down by Earth Alliance security forces.

In "Babylon Squared,"
Babylon 4 -- the biggest of the Babylon stations, which
dissapeared 24 hours after coming online, suddenly reappeared.
Delenn was chosen by the Grey Council to be their new leader, but
declined because a Minbari prophecy told her that her destiny was on
Babylon 5. She left with a powerful device called a triluminary. On
Babylon 4, as time disturbances flashed back and forward to other times
(including a scene where
something was coming through the walls of the station, being fought off by
Garibaldi, as Sinclair was pushed into the crowds), the crew attempted to
evacuate the crew of B4. A mysterious alien, Zathras, appeared and told
of a great, terrible war, and the attempt to pull B4 through time to use it
as a base of operations. Zathras was looking for "The One" -- the great leader
of an effort to bring peace to the galaxy. Babylon 4 was evacuated, but
Zathras, trapped, was rescued by "The One" -- who turned out to be a much older
Sinclair, aided apparently by Delenn.